Lack of association between stroke symptom knowledge and intent to call 911: a population-based survey.

Excessive prehospital delay between acute stroke onset and hospital arrival is an ongoing problem. Translating knowledge of stroke warning signs into appropriate action is critical to decrease prehospital delay. Our objectives were to estimate the proportion of Michigan adults who would react appropriately by calling 911 when presented with hypothetical stroke-related scenarios and to examine the association between knowledge of warning signs and calling 911. In 2004, questions regarding initial response to health-related scenarios were added to the Michigan Behavioral Risk Factor Survey, a population-based telephone survey of adults. We calculated the proportion of respondents who would call 911 in response to 3 stroke-related scenarios and examined the association between stroke warning sign knowledge and 911 activation. Among 4841 adults, 27.6% (95% CI, 26.2 to 29.0) had adequate knowledge of stroke warning signs (defined as reporting 3 correct warning signs), and 14.0% (95% CI, 12.9 to 15.1) reported they would call 911 for all 3 stroke-related scenarios. Knowledge of specific stroke warning signs was only modestly associated with calling 911 in response to medical scenarios that involved the same stroke symptom (OR, 1.17 to 1.39). Even among those with adequate knowledge of stroke warning signs, only 17.6% (95% CI, 15.5 to 20.0) would call 911 for all 3 stroke scenarios. In this population-based survey, stroke symptom knowledge was not associated with the intent to call 911 for stroke. This study emphasizes the critical role of motivation in addition to symptom knowledge to reducing delay time to hospital arrival for stroke.